My DIY phase change system :D

Today I made up a evaporator for my phase change unit I found on the side of the road. The shop closed before I got a chance to take it back to get it filled, so I tried something else instead. I connected the evaporator to the suction line, and released the valve to flush the air (or most of it) from the evaporator. I then connected it to the inlet, and opened both valves. Fired it up and it works

Of course, since it hasn't been regassed yet, it's running on low refrigerant, and thus freezing up a lot more than it should, but the compressor does not seem worried yet. The accumulator and line right up to the compressor is frozen up, but it's not showing signs of getting liquid. I know running it like this in the long run would be bad, and I intend to get it gassed properly, but it's OK for now

I'm unsure as to why this unit was dumped, theres nothing wrong with it.

Anyways, anyone need a couple (hundred) diode bars cooled? My brother has already found a use for it . I intend to use antifreeze or something and use it to chill fog when needed, and maybe to cool my bro's and mums room during summer.







It's a 3.5kW unit.

Cheers,
Dan

I can't seem to tell... Is the ENTIRE copper pipe frozen? :S

Yep, the whole thing is a big chunk of ice. I'll have a pic of it about an hour later up in a few minutes.

Rofl, is that a toy car?

It is

lawl, now hit it with a hammer!

Turned it off about 1/2 an hour after that pic, by that point all the pipes out of the water where completely frosted over, and the compressor started giving hints of liquid entry.

I'm going to make a temp control system, probably with an ATMega and use a little LCD to display temp. Then use LM335's placed on the compressor, coils, in the water etc. Code it to operate a relay to turn the compressor on/off etc.

Going by how fast I got my finger stuck on the pipe before I put it under water, my guesstimation is that it's pretty cold

I bought a temperature controller today, hooked it up and it worked. Well, I unplugged the unit, and totally forgetting you need to give it a bit of time for the pressure to stabilize, plugged it back in. 1 or 2 seconds later, a fireball complete with sparks erupted from my triac. I guess thats what you get when you try pull 240V @ over 30A thru a 600V 8A triac



I've remade the circuit to switch a relay instead, but I think the opamp is blown somehow. Oh well, I'll get it sorted out ...

take it back to jaycar and say "umm this thing is broken" hheheheh there are some funny people at jaycar :crackup:

Nice find... its it just the outdoor part of a split-system AC, or one of those units you're supposed to mount through a window/wall as a whole?

Yep, just the outdoor part of a split system

Really cool build - we tried to do something like this to repair our split system for a data center a while back. Not so much luck. It's cool that yours works..

Damn. I wonder who would just leave that on the side of the road - or- are you at liberty to give more details on how you found it?

I'm never that lucky; Someone I knew back in the 90s actually found a *WORKING* Lexel 88 ArIon head and controller being thrown out in an industrial district. He got it working, and then while he was out, his roommate decided to 'show it to some friends' -- but neglected to turn on the water. Beam for a second or two, then - crack.

Interesting thought: I live near REO; I wonder what dumpster diving there would yield

aryntha said:

I'm never that lucky; Someone I knew back in the 90s actually found a *WORKING* Lexel 88 ArIon head and controller being thrown out in an industrial district. He got it working, and then while he was out, his roommate decided to 'show it to some friends' -- but neglected to turn on the water. Beam for a second or two, then - crack.

Click to expand...

That friend would have been punched in the face :yabbmad: and possibly had his wallet taken the next time he fell asleep...:yabbmad::yabbmad::yabbmad:

Perhaps the conduits had failed on that AC, and the owner dumped the outdoor part of it, leaving the indoor part in place to replace the tubing... or chose not to repair it at all, and just use the indoor unit is a fan.

My guess is they simply upgraded to a larger unit. The fact the valves were closed and it still contained gas indicates it was removed by a professional.

As to where I found it, it really was just on the side of the road.

I'm going to add a LCD screen and a microcontroller inside the case. That way I can program it to monitor temps, turn the unit on and off, as well as the vital 3 minute delays on power up. With 6 analog inputs, I can have it measure 6 temperatures all at once Although I'd really only need maybe 2 or 3.